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                <ol class="chapter"><li class="chapter-item expanded "><a href="architecture.html"><strong aria-hidden="true">1.</strong> Architecture</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="boot_process.html"><strong aria-hidden="true">1.1.</strong> Boot Process</a></li><li class="chapter-item expanded "><a href="filesystem_layout.html"><strong aria-hidden="true">1.2.</strong> MLL ISO Image Structure</a></li></ol></li><li class="chapter-item expanded "><a href="overview.html"><strong aria-hidden="true">2.</strong> Shell Scripts &amp; Folders</a></li><li class="chapter-item expanded "><a href="build_scripts.html"><strong aria-hidden="true">3.</strong> Build Process</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="config_file.html"><strong aria-hidden="true">3.1.</strong> Configuration File</a></li><li class="chapter-item expanded "><a href="common.html" class="active"><strong aria-hidden="true">3.2.</strong> Common Properties &amp; Functions</a></li><li class="chapter-item expanded "><a href="00_clean.html"><strong aria-hidden="true">3.3.</strong> Step 00 - Clean Workspace</a></li><li class="chapter-item expanded "><a href="01_get_kernel.html"><strong aria-hidden="true">3.4.</strong> Step 01 - Get Kernel</a></li><li class="chapter-item expanded "><a href="02_build_kernel.html"><strong aria-hidden="true">3.5.</strong> Step 02 - Build Kernel</a></li><li class="chapter-item expanded "><a href="03_get_glibc.html"><strong aria-hidden="true">3.6.</strong> Step 03 - Get GLIBC</a></li><li class="chapter-item expanded "><a href="04_build_glibc.html"><strong aria-hidden="true">3.7.</strong> Step 04 - Build GLIBC</a></li><li class="chapter-item expanded "><a href="05_prepare_sysroot.html"><strong aria-hidden="true">3.8.</strong> Step 05 - Prepare Sysroot</a></li><li class="chapter-item expanded "><a href="06_get_busybox.html"><strong aria-hidden="true">3.9.</strong> Step 06 - Get Busybox</a></li><li class="chapter-item expanded "><a href="07_build_busybox.html"><strong aria-hidden="true">3.10.</strong> Step 07 - Build Busybox</a></li><li class="chapter-item expanded "><a href="08_prepare_bundles.html"><strong aria-hidden="true">3.11.</strong> Step 08 - Prepare Bundles</a></li><li class="chapter-item expanded "><a href="09_generate_rootfs.html"><strong aria-hidden="true">3.12.</strong> Step 09 - Generate Rootfs</a></li><li class="chapter-item expanded "><a href="10_pack_rootfs.html"><strong aria-hidden="true">3.13.</strong> Step 10 - Pack Rootfs</a></li><li class="chapter-item expanded "><a href="11_generate_overlay.html"><strong aria-hidden="true">3.14.</strong> Step 11 - Generate Overlay Structure</a></li><li class="chapter-item expanded "><a href="12_get_syslinux.html"><strong aria-hidden="true">3.15.</strong> Step 12 - Get Syslinux</a></li><li class="chapter-item expanded "><a href="12_get_systemd-boot.html"><strong aria-hidden="true">3.16.</strong> Step 12 - Get systemd-boot</a></li><li class="chapter-item expanded "><a href="13_prepare_iso.html"><strong aria-hidden="true">3.17.</strong> Step 13 - Prepare ISO Structure</a></li><li class="chapter-item expanded "><a href="14_generate_iso.html"><strong aria-hidden="true">3.18.</strong> Step 14 - Generate ISO Image</a></li><li class="chapter-item expanded "><a href="15_generate_image.html"><strong aria-hidden="true">3.19.</strong> Step 15 - Generate Filesystem Image</a></li><li class="chapter-item expanded "><a href="16_cleanup.html"><strong aria-hidden="true">3.20.</strong> Step 16 - Final Cleanup</a></li></ol></li></ol>
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                    <h1 class="menu-title">Minimal Linux Live</h1>

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                        <h1><a class="header" href="#common-properties-and-functions" id="common-properties-and-functions">Common Properties And Functions</a></h1>
<ul>
<li><a href="#properties">Properties</a></li>
<li><a href="#functions">Functions</a></li>
</ul>
<hr />
<p>The shell script file <a href="https://github.com/ivandavidov/minimal/blob/master/src/common.sh">common.sh</a> is sourced in all MLL scripts. It provides common properties and functions.</p>
<h2><a class="header" href="#properties" id="properties">Properties</a></h2>
<h4><a class="header" href="#src_dir" id="src_dir">SRC_DIR</a></h4>
<p><code>SRC_DIR=src/</code></p>
<p>This is the main source directory, i.e. the property references the main project directory <code>src/</code>.</p>
<h4><a class="header" href="#config" id="config">CONFIG</a></h4>
<p><code>CONFIG=src/.config</code></p>
<p>This is the main configuration file. The configuration properties are described <a href="TODO...">here</a>. </p>
<h4><a class="header" href="#source_dir" id="source_dir">SOURCE_DIR</a></h4>
<p><code>SOURCE_DIR=src/source/</code></p>
<p>This is the directory where all source archives are downloaded. </p>
<h4><a class="header" href="#work_dir" id="work_dir">WORK_DIR</a></h4>
<p><code>WORK_DIR=src/work/</code></p>
<p>This is the directory where all MLL artifacts are processed. All build actions happen in this directory. </p>
<h4><a class="header" href="#kernel_installed" id="kernel_installed">KERNEL_INSTALLED</a></h4>
<p><code>KERNEL_INSTALLED=src/work/kernel/kernel_installed/</code></p>
<p>This is the directory where the kernel and its corresponding header files are placed after the kernel build phase has been completed. </p>
<h4><a class="header" href="#glibc_objects" id="glibc_objects">GLIBC_OBJECTS</a></h4>
<p><code>GLIBC_OBJECTS=src/work/glibc/glibc_objects/</code></p>
<p>This is the directory where the GNU C Library is going to be built.</p>
<h4><a class="header" href="#glibc_installed" id="glibc_installed">GLIBC_INSTALLED</a></h4>
<p><code>GLIBC_INSTALLED=src/work/glibc/glibc_installed/</code></p>
<p>This is the directory where the GNU C Library shared objects (.so files) are placed after the build phase has been completed.</p>
<h4><a class="header" href="#busybox_installed" id="busybox_installed">BUSYBOX_INSTALLED</a></h4>
<p><code>BUSYBOX_INSTALLED=src/work/busybox/busybox_installed/</code></p>
<p>This is the directory where Busybox is placed after the build phase has been completed.</p>
<h4><a class="header" href="#sysroot" id="sysroot">SYSROOT</a></h4>
<p><code>SYSROOT=src/work/sysroot/</code></p>
<p>The system root folder for MLL. This folder contains GLIBC, and kernel header files. MLL uses the sysroot folder in order to properly link Busybox with the custom built kernel and GLIBC. </p>
<h4><a class="header" href="#rootfs" id="rootfs">ROOTFS</a></h4>
<p><code>ROOTFS=src/work/rootfs/</code></p>
<p>This folder contains the rootfs/initramfs structure which is generated by the core MLL build process.</p>
<h4><a class="header" href="#overlay_rootfs" id="overlay_rootfs">OVERLAY_ROOTFS</a></h4>
<p><code>OVERLAY_ROOTFS=src/work/overlay_rootfs/</code></p>
<p>This folder contains the rootfs/initramfs structure which is generated by the overlay subsystem build process.</p>
<h4><a class="header" href="#isoimage" id="isoimage">ISOIMAGE</a></h4>
<p><code>OVERLAY_ROOTFS=src/work/isoimage/</code></p>
<p>This folder contains the final ISO image structure.</p>
<h4><a class="header" href="#isoimage_overlay" id="isoimage_overlay">ISOIMAGE_OVERLAY</a></h4>
<p><code>OVERLAY_ROOTFS=src/work/isoimage_overlay/</code></p>
<p>This folder contains the final overlay subsystem ISO structure.</p>
<h2><a class="header" href="#functions" id="functions">Functions</a></h2>
<h4><a class="header" href="#read_propertyprop_name" id="read_propertyprop_name">read_property(prop_name)</a></h4>
<p>This function reads properties from the main <code>.config</code> file.</p>
<pre><code class="language-bash"># Example

JOB_FACTOR=`read_property JOB_FACTOR`
</code></pre>
<h4><a class="header" href="#download_sourceurl-file_to_save" id="download_sourceurl-file_to_save">download_source(url, file_to_save)</a></h4>
<p>This function downloads the <code>url</code> resource and saves it as <code>$file_to_save</code>.</p>
<pre><code class="language-bash"># Example
#
# This is the filesystem structure before the execution
# of the function.
#
# src/
# └── source/
#     └── (no files/folders)

download_source \
  'https://busybox.net/downloads/busybox-1.32.0.tar.bz2' \
  $SOURCE_DIR/busybox-1.32.0.tar.bz2
  
# This is the filesystem structure after the execution
# of the function.
#
# src/
# └── source/
#     └── busybox-1.32.0.tar.bz2
</code></pre>
<h4><a class="header" href="#extract_sourcearchive_file-dest_dir" id="extract_sourcearchive_file-dest_dir">extract_source(archive_file, dest_dir)</a></h4>
<p>This function extracts the archive <code>archive_file</code> in the directory <code>src/work/$dest_dir/</code>.</p>
<pre><code class="language-bash"># Example
#
# This is the filesystem structure before the execution
# of the function.
#
# src/
# ├── source/
# │   └── busybox-1.32.0.tar.bz2
# └── work/
#     └── (no files/folders)

extract_source \
  $SOURCE_DIR/busybox-1.32.0.tar.bz2 \
  busybox
  
# This is the filesystem structure after the execution
# of the function.
#
# src/
# ├── source/
# │   └── busybox-1.32.0.tar.bz2
# └── work/
#     └── busybox
#         └── busybox-1.32.0/
</code></pre>

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